Drive mechanism



June 10, 1941.

.1. E. PADGETT DRIVE MECHANISM Filed Oct. 28, 1938 2 Sheets-Sheet 1INVENTOR. JUMP/1' PADc-z-Er ma'Z/m ATTORNEY 2 Sheets-Sheet 2 INVENTOR.JOSEPH/ P/weffr ATTORNEY June 10, 1941 J. E. PADGl-:TT

DRIVE MECHANISM Filed Oct. 28, 1938 Petented June 1o, 1941 Joseph E.Padgett, Toledo, ohio Application October 2.8, 1938, Serial No. 237,457

1 Claim. (Cl

This invention relates lto automotive vehicles and is more particularlydirected to improved drive or power transmission mechanisms for suchvehicles.

An object of the invention is to provide a novel drive mechanism inwhich the transmission and differential are enclosed in a compact casingstructure supported adjacent the driving wheels, and rspaced from thepower plant which is connected thereto by means of a propeller shaft.

Another object of the invention is to provide an improved unitarytransmission and differential assembly for use in adrive mechanism ofthis type which is wholly contained in anI integral casing of minimumsize and adapted tovbe readily removable for repair or replacement.

A further object of the invention'is to provide an improved casingstructure in which the supporting surfaces or seats of the severalbearings used to mount the input shafts, the combined countershaftandfpinion shaft and the differential carrier, are all formed directlyon the casing walls, thereby facilitating manufacture and providing astronger, yet lighter and improved assembly. I

A still further object of the invention is to provide a novel andimproved transmission differential unit wherein the power input shaft ofthe l transmission is extended beyond the differential for use as apower take-off shaft.

A further object of the invention is to provide a transmissiondifferential unit for a vehicle in which a separate power take-olf shaftis arranged substantially in line with the axis of the differential ringgear, the Stake-oil shaft being selectively operable from the primarytransmission shaft.

Further objects and advantages of the invention will become apparentfrom a study of the following descriptiontaken in connection with theaccompanying drawings, in which:

Figure 1 is a longitudinal vertical sectional view of a form of theinvention;

Figure 2 is a. vertical sectional view taken substantially on a line2--2 of Figure 1; and

Figure 3 is a view 'similar to Figure 1, illustrating another form ofthe invention.

With reference to the drawings, wherein like reference characters areused to designate the l same parts wherever they occur throughout theseveral views, an axle drive assembly has been illustrated as comprisinga casing portion I5 preferably formed as a metal casting having integraloppositely extending projections I1 and I8 and an integral extension I9projecting in angular relation. The assembly also includes change speedgearing and differential mechanism, the latter being vdriven by aunitary countershaft and pinion shaft withinthe unitary casing, and thecasing being formed with interior bearing seats for supporting suitablebearings which cooperate to absorb end thrust and radial loads.

The projections I1 and I8 are constructed so as to form mounts for axletubes 2| and 22 which extend outwardly from the casing I5, the outerextremities of the tubes serving to locate the usual wheel structures.When desired, the projections I1 and I8 may be projected or extendedoutwardly to the wheels, in which instance the tubes 2| and 22 may beeliminated. The axle tubes when utilized may be secured in theprojections in any suitable manner as by welding or riveting andlikewise the tubes or the projections may be of anydesired lengthdepending upon the type of vehicle with which the structure is used.

A propeller shaft, (not shown) is` preferably connected between asuitable source of power and the input end of the unitary transmissionand differential mechanism 21. Suitable shifting mechanism is mountedadjacent the change speed gearing of unit 21, and may be in the form ofa conventional shifting lever or 'by remotely controlled automaticshifting means, depending upon the type of vehicle with vwhich theinvention is utilized.A

Referring now to the form of the invention shown in Figures 1 and 2, thepower transmission unit 21 comprises the integral casing structure I5having front and rear sections 13 and 15 separated by wall 11. In someinstallations a.

flange 19 may be provided which surrounds the unit 21 and is providedwith a locating and supporting surface 8|' adapted to be bolted to acasing or other supporting element (not shown).

Cover 88 closes an opening in the top of section 13 andV may' beprovided with a gear shift lever 29, in the manner shown.

Shaft is journaled in the casing on bearings 81, 89 and 9|, with cap 83,under which are adjusting shirns 96, serving to hold bearings 81- 89 andshaft 85 in assembled position. Sealing means prevents the escape oflubricant from thel casing through cap 33. Gears 31, 89 and |0| aresplined on shaft 85, spacing ring |03 and snap ring |05 serving toposition these gears axially on shaft 85. Shaft 85 is splined at 98 toreceive a universal joint of the propeller shaft.

Directly below, and parallel to,`shaft 85 is a second splined shaft |01,journaled in bearings |09 and III. Gear I| 3 is formed integrally withshaft |01 and nut |I5 holds theouter races of bearings |03, againstshoulders in the casing.

shims ||1 and IIS/being employed to adjust the bearing clearances.

|25 which are adapted to be selectively meshed with gears 91, 99 and |5|by a shifting mechaeral, three forward and`one reverse, speeds'in anobvious manner.

Bevel ring gear l3|, shown in broken lines in Figure 1, meshes withpinion ll3, carried by shaft |01, and is mounted on a. differentialcarrier member |33, journaled in bearings |35, |31.

Bearings |35, |31 are mounted in bearing supports |39, |4|, formed onthe interior of casing section 15, by means of caps |43, |45, held in`place by nuts |41. Annular thrust surfaces |45, |40, are formedl on thewalls of casing 15 to sustain the axial thrusts of bearings |35, |31.Differential pinion gears |49 drive side gears l5l. to which are splinedthe axle vshafts or drive axles 51-51. Axles 51-51 extend outwardly fromcasing 15 through sealing means |53-|53.

Thel rear face of casing portion 15 is closed by cover |55, formed witha projecting portion |51 to which is detachably secured a closure |55surrounding a projecting end of shaft 55. The projection |51 is tapered,as shown, and the closure |53 is made of resilient material and split,as at |63, so that it may be readily removed or snapped into place -withthe shoulder v|5l abutting the end of projection |51. Y

'I'he portion 15 of the casing is generally circular, see Figure 2, andwhen the structure is utilized in a tractor, for example, having `atransverse rear housing or supporting structure which carries the naldrive, the portion 15 may be secured therein by suitable bolts, passingthrough the holes |51 to hold the unit 21 in place. When thus assembledthe closure l5! projects out.- wardly, the projecting end of shaft 55,enclosed by closure |59 being formed with keyways |55, so that suitaiblepower take-on devices may be secured thereto when closure |55 isremoved.

The uni-t 21, as will be noted, is integral and by simply sliding. theshafts 51-51 out of the unil'l it may be readily removed for replacement`or repair. It will also be observed that as the bearing seats are allformed directly in the casing walls to absorb end thrust and radialloads, the sizes of gears l3|, 51, 55, l0|, |21, |23 and |25 may bereducedrand the overall size of the 'whole unit correspondingly reduced.Also by Slidably mounted on the splined shaft |01 are three gears |2l,|23 andf` extending the shaft 55, see Figure 1, a convenlent powertake-off, housed by the closure |55 when not in use, is provided.

Turning now to Figure 3, a modified form of unitary power transmissiondevice, incorporating all ofthe features of the construction justdescribed, but designed to be mounted on a slightly different form ofaxle element, is dis closed. e

In this embodiment. of my invention, casing 25| is provided with anintegral lug or projection 253, which is recesed at 255 to form ananchorage for a drawbar, or milar device, used to attach implementspulled behind a tractor, for example, when the invention is used in suchA a vehicle. Shaft 255 is :lournaled in casing 25| hearing 75' bybearlngszll, zu, and als, the iatteither description 2,245,018 y L 215and 22| are formed .integrally with. shaft2|l5 while gears 223, 225 andkeyed thereon. Gear 221 is also'keyed to shaft 259. Bearing cap 223holds bearing 2|3 in the housing 25|, while spacing sleeve 23|,interposed between gear 221 and a power receiving element, 235,transmits the thrust of a clamping nut 233 throughout the wholeassembly. y Gear 221 drives a conventional power pulley, not shown.

Shaft 231, arranged below and parallel to shaft 255, is journaled inbearigsffand 24|. Rotatably mounted on shaft 231 aregears 253, 245 and241, while splined thereto is a. clutch element 245 and gear 25|. Gear243 is mounted on a bushing element 253 and a nut 255 thrusts vthe innerrace of bearing 24| against the bushing 253 and also serves to holdbearings 24| and 233, as well as shaft 231, in assembled position. Gears243 and 245 are provided with sets of "clutch teeth 251v and 253,respectively, and a sliding clutch element 26| is mounted on clutchelement 253 for engagement with either of the' sets of teeth' 251 and259. Gear 241 is provided Y 'with external clutch teeth 253 arranged tocooperate with internal teeth 254, carried by the gear 25|.

By means ofa` shifting mechanism, not shown, controlled by the lever255, mounted in cover 251, anyone of] the gears 243, 245 or 241, whichconstantly mesh with gears 22|, mici 22s, may be drivingly connected toshaft 231. Also by sliding gear 25| to the left, from its positionVshown in Figure 3, it maybe meshed with an idler gear, not shown.driven by gear 2l9, to give a reverse drive. This type of variable speedtransmission is well known in the art, and furthereof is,y therefore,vdeemed unnecessary. f Y

In this modification, a signify different form of power take-off isprovided by? extending shaft 255 a short distance beyond the bearing2|3. A removable end portion 355 is secured to flange 351 by boltspassing through suitable openings and carries shaft 3|| and bearings3|3. Shaft 3I| is journaled in bearings 3| 5, 3|1, the latter of whichis sealed by 'a stumng box 3|9, and carries a gear 32|. A shaft 323 isjournaled at one end in bearing 3|3 and connected by coupling 325 to theextending portion of shaft 255. splined to shaft 323 is a slideable gear321, adapted to be selectively meshed with gear 32| by a shifting meansnot shown. This the shaft 3|| provides a power take-off which may beselectively driven at any time when the vehicle engine with differenttypes of rear axle elements in a very flexible manner, it being onlynecessary to slightly modify the construction of the casing.

- It will also be seen that when my improved unit is associated with thedriving axle element of a Vvehicle with the differential mechanismdirectly improved units, no material lengthening of the being carriedbyaprojecting-Portion 2U. Gears over the center-line of the axle element, aconsiderable space is left back of the engine clutch and between it andthe front of the power transl mission unit. Due 'to the .compactness ofmy usual frame structure is required to obtain these results. l

In addition it will be observed that in each modification the surfacesfor receiving and supporting the several bearings are formed-directly onthe casing structure. Thus in the modincation shown in Figures 1 and 2the radial supporting surfaces for the diflerentialrcarrier bearV ingsare machined on the supports Iii-lll, see Figure 2, while in themodification shown in Figure 3, the corresponding radial supportingsurfaces are formed in corresponding supports. In each modication axialthrust surfaces are provided on the casing side-walls, see Mil-|40 ofFigure 2. Likewise the supporting surfaces for bearings 8l, 89, |09 andwhich support the shafts 85 and |01, and also the supporting surfacesfor bearings 2 I, 2|3, 238 and 24|, which support shafts 259 and 231,are machined direct- 1y on the casings IE and 20|, respectively.

- The foregoing arrangementnot only provides an unusually rigid andstrong construction but also makes it possible to very accurately locatethese bearing supporting surfaces by simple machining operations andinsures uniformity in production. The bearing supporting surfaces forthe diiierential carrier bearings may, be formed in the manner shown inthe patent to Joseph E. Padgett and Robert P. lewis, Reissue .No.20,149, granted October 27, 1936, if desired.

When the present invention is incorporated for use in tractors, forexample, the housing extensions may be extended to gear trains at theWheels, in which instance reduction gearing is preferably interposedbetween the ends oi the axles and the wheels through which the maiorpart or the speed reduction may be enacted. Such an arrangement makes itpossible to reduce the casing into front and placement.

the size of the bevel ring gear and thus keep the` size ot the unit downto the desired minimum.

Also in both embodiments. the unit may be easily removed from thetractor for repair or re- This is of considerable importance as vehiclesof this type are subjected to unusually severe operating conditionsunder the care of unskilled persons.

The invention mayI be embodied in other specic forms without departingfrom the spirit or essential characteristicsv thereof. The presentembodiments are therefore to be considered in all respects asillustrative and not restrictive, the scope ofthe invention beingindicated by the appended claim. rather than by the ioregof ingdescription, and al1 changes which come within the meaning and range ofequivalency oi the claim are therefore intended to be embraced therein.

What is claimed and desired to be secured by United- States LettersPatent is:

In a unitary power transmission device, an integral casing. a transverseinner wall dividing rear compartments, said rear compartment having anopen end, an axle tube mount integral with and extending from each sidevci said rear compartment, a closure for the open end of said rearcompartment, and a mounting fiange for said casing forming a radialextension of said inner wall.

JOSEPH E. PADGETI.

